351 citations · 1.3k across the 24 of their papers we have counts for
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Lorentz Invariance Violation and the Observed Spectrum of Ultrahigh Energy Cosmic Rays
S. T. Scully, F. W. Stecker
There has been much interest in possible violations of Lorentz invariance, particularly motivated by quantum gravity theories. It has been suggested that a small amount of Lorentz…
The Spectrum of 1ES0229 + 200 and the Cosmic Infrared Background
F. W. Stecker, and S. T. Scully
We examine the effect of gamma-ray absorption by the extragalactic infrared radiation on intrinsic spectra predicted for 1ES0229+200 and compare our results with the observational…
Corrected Table for the Parametric Coefficients for the Optical Depth of the Universe to Gamma-rays at Various Redshifts
F. W. Stecker, M. A. Malkan, S. T. Scully
Table 1 in our paper, ApJ 648, 774 (2006) entitled "Intergalactic Photon Spectra from the Far IR to the UV Lyman Limit for 0 < z < 6 and the Optical Depth of the Universe to High E…
A Simple Analytic Treatment of the Intergalactic Absorption Effect in Blazar Gamma-ray Spectra
F. W. Stecker, S. T. Scully
We derive a new and user friendly simple analytic approximation for determining the effect of intergalactic absorption in the energy range 0.2-2 TeV and the redshift range 0.05-0.4…
Intergalactic Photon Spectra from the Far IR to the UV Lyman Limit for and the Optical Depth of the Universe to High Energy Gamma-Rays
F. W. Stecker, M. A. Malkan, S. T. Scully
We calculate the intergalactic photon density as a function of both energy and redshift for 0 < z < 6 for photon energies from .003 eV to the Lyman limit cutoff at 13.6 eV in a Lam…
Lorentz Invariance Violation and the Spectrum and Source Power of Ultrahigh Energy Cosmic Rays
F. W. Stecker, S. T. Scully
Owing to their isotropy, it is generally believed that ultrahigh energy cosmic rays (UHECRs) are extragalactic in origin. It is then expected that interactions of these cosmic rays…
Error estimation for the MAP experiment
S. Prunet, R. Teyssier, S. T. Scully +2
We report here the first full sky component separation and CMB power spectrum estimation using a Wiener filtering technique on simulated data from the upcoming MAP experiment, set…
On the spectrum of Ultrahigh Energy Cosmic Rays and the Gamma Ray Burst Origin Hypothesis
S. T. Scully, F. W. Stecker
It has been suggested that cosmological gamma-ray bursts (GRBs) can produce the observed flux of cosmic rays at the highest energies. However, recent studies of GRBs indicate that…
Light Element Evolution and Cosmic Ray Energetics
R. Ramaty, S. T. Scully, R. E. Lingenfelter +1
Using cosmic-ray energetics as a discriminator, we investigate evolutionary models of LiBeB. We employ a Monte Carlo code which incorporates the delayed mixing into the ISM both of…
A Bayesian Estimate of the Primordial Helium Abundance
Craig J. Hogan, Keith A. Olive, Sean T. Scully
We introduce a new statistical method to estimate the primordial helium abundance, Y_p from observed abundances in a sample of galaxies which have experienced stellar helium enrich…
Low Mass Stars and the He3 Problem
Keith A. Olive, D. N. Schramm, Sean Scully +1
The prediction of standard chemical evolution models of higher abundances of He3 at the solar and present-day epochs than are observed indicates a possible problem with the yield o…
The Effects of an Early Galactic Wind on the Evolution of D, \he3 and Z
Sean Scully, Michel Cassé, Keith A. Olive +1
The predictions of the abundances of D and \he3 from Big Bang Nucleosynthesis (BBN) and recent observations of these two isotopes suggest the need to develop new chemical evolution…
The Local Abundance of He: A Confrontation Between Theory and Observation
Sean T. Scully, Michel Casse, Keith A. Olive +3
Determinations of the \he3 concentrations in Galactic matter serve to impose interesting and important constraints both on cosmological models and on models of Galactic chemical ev…
Big Bang Nucleosynthesis: An Update
Keith A. Olive, Sean T. Scully
WThe current status of big bang nucleosynthesis is reviewed with an emphasis on the comparison between the observational determination of the light element abundances of \D, \he3,…
The Deuterium Abundance and Nucleocosmochronology
Sean Thomas Scully, Keith A. Olive
We examine galactic chemical evolution models which reproduce the present-day and pre-solar values of deuterium starting with a primordial value which is consistent with a baryon-t…
Neutrino Process Nucleosynthesis and the B/B Ratio
Keith A. Olive, Nikos Prantzos, Sean Scully +1
We consider the evolution of the light elements ( and ) incorporating the effects of their production by both neutrino process and cosmic-ray nucleosynthesis. We test th…